1. Field of the Invention
The present invention relates to an apparatus for ventilating spacious public rooms, workshops, industrial halls, underground parking lot and the like spaces, and more particularly to an apparatus having a damper for adjusting air supply which effectively reduces air resistance, and a nozzle having a plurality of guide vanes which swirl injected ventilation air supplied to the rooms.
2. Description of the Prior Art
As shown in FIGS. 1 to 3, conventional ventilating apparatus of the aforementioned type, for example, is comprised of a damper 10 having shutter plate 12 provided within and across tubular body 11 and operable to rotate for controlling quantity of the air flow passing through the tubular body by operating actuating shaft 14, a end cap 20 formed with extended portion 21,outwardly folded portion 22 and insertion groove 23, a connecting tube 30 having gaskets 31 provided in both ends thereof, a bellows tube 50 connected between the end cap 20 and the connecting tube 30, and a nozzle 40 formed with opening 42 and elongated outlet 41 for injecting air supply from the main duct into the rooms.
The damper 10 is mounted to the tubular branch duct 61 formed in the main duct 60 by inserting one end of the tubular body 11 with gasket 13 into the branch duct 61 and fastening the junction with proper locking means. Further, one end of the bellows 50 is inserted into the groove 23 of the end cap 20, and the end cap 20 is mated with the other end of the tubular body 11 with gasket 13 and fastened along the outwardly folded portion 22. Similarly, the other end of the bellows 50 is coupled with the nozzle 40 which is mated with the connecting tube 30 by insertion of the other end of bellows through the connecting tube 30 and gaskets 31 into the opening 42 of the nozzle 40.
Such an apparatus is preferably connectable in series to a duct installation of ventilating system, as an ejector, which supplies warm or cold air fed from a separate air conditioning means, or supplies ventilation air from a separate blower.
Referring to FIGS. 2 and 3, the shutter plate 12 of the damper 10 is provided with the actuating shaft 14, and is capable of adjusting flow rate in the tubular body 11 by rotating the shaft 14 with appropriate electromechanical actuating means,for example solenoid magnet unit,etc.
The divergent flow of injected air or jet from the nozzle 40 of the apparatus in the spaces has predetermined extent and diffusion angle if the temperature of ventilation air and that of room air have the same value. Otherwise, the divergent flow will vary, particularly in winter or summer. For this reason, there is occurred phenomena of cold draft and air pocket in summer, which caused discomfort to dweller. Further, it is found that the ventilation and/or air conditioning efficiency was lowered in winter since the stagnation zone was formed above dwelling zone by the effect of thermal buoyancy.
Furthermore, as the shutter plate 12 adjusting the air supply is provided perpendicularly across the tubular body 11, and if the shutter plate 12 is controlled and opened to a little amount, it per se suffers considerable supply air pressure and much noise is occurred by turbulent flow around the plate. Therefore, positive pressure of supply fan should be increased such that it compensates for the loss of positive pressure, as well as rotation friction of the actuating shaft 14 supporting the shutter plate 12 should be considerably high so as to stablely keep the controlled rotated position. Thereby, it is difficult to drive the actuating shaft 14 and to exactly adjust air flow when the damper is required to be controlled. In addition, since there was not provided a flow detecting means for measuring quantity of air flow through the damper 10, the adjustment of flow rate was based upon the design or human experience that resulted in undesirable ventilating or air conditioning as well as unnecessary energy consumption.
The present invention is directed to solving the problems of the prior art by providing a precisely adjustable, energy efficient, non-turbulent damper assembly which avoids the noise, control difficulties,and energy waste of the prior art apparatus, and a nozzle which has a unique design to create swirl in jet or in injected ventilation air supplied to the rooms.